There are two types of crosstabs:
Dynamic
Static
With dynamic crosstabs, PowerBuilder builds all the columns and rows in the crosstab dynamically when you run the crosstab. The number of columns and rows in the crosstab match the data that exists at runtime.
Using the preceding crosstab as an example, if a new printer was added to the database after the crosstab was saved, there would be an additional row in the crosstab when it is run. Similarly, if one of the quarter’s results was deleted from the database after the crosstab was saved, there would be one less column in the crosstab when it is run.
By default, crosstabs you build are dynamic.
Static crosstabs are quite different from dynamic crosstabs. With static crosstabs, PowerBuilder establishes the columns in the crosstab based on the data in the database when you define the crosstab. (It does this by retrieving data from the database when you initially define the crosstab.) No matter what values are in the database when you later run the crosstab, the crosstab always has the same columns as when you defined it.
Using the preceding crosstab as an example, if there were four quarters in the database when you defined and saved the crosstab, there would always be four columns (Q1, Q2, Q3, and Q4) in the crosstab at runtime, even if the number of columns changed in the database.
Dynamic crosstabs are used more often than static crosstabs, for the following reasons:
You can define dynamic crosstabs very quickly because no database access is required at definition time.
Dynamic crosstabs always use the current data to build the columns and rows in the crosstab. Static crosstabs show a snapshot of columns as they were when the crosstab was defined.
Dynamic crosstabs are easy to modify: all properties for the dynamically built columns are replicated at runtime automatically. With static crosstabs, you must work with one column at a time.
